The present invention is directed to construction toy sets, and more particularly to improvements in construction toy sets of the type in which the components are individual blocks formed with projecting studs and/or recesses to enable assemblies to be constructed by joining projecting studs of one block with recesses of another.
In general, construction toys utilizing blocks with studs and recesses are well known and are commercially available. The present invention is directed to improved features in building blocks of this general type, to the end of making them easier and more desirable to use, more securely joined when assembled, yet readily disassembled when desired.
In a preferred form of the invention, individual building blocks are comprised of upper and lower shells, formed of injection molded plastic, which are joined together, preferably permanently, to form a lightweight, hollow block. For convenience, but without intending any limitation, one of the halves may be referred to herein as the top and the other as the bottom.
One or more studs, integral with the top of the block, extend upward therefrom and, in a preferred embodiment, a corresponding number of recesses of similar configuration are formed in the bottom of the block. It is also contemplated that, in certain cases, blocks may be provided with only studs or only recesses, or with studs and recesses in different number.
Although other configurations are possible and contemplated within the basic teachings of the invention, in a particularly preferred and advantageous form of the invention the studs and recesses are configured in the form of equilateral octagons. In each block, the studs and recesses are of equal number and are arranged in coaxial pairs, with each stud being coaxial with a corresponding recess on the opposite side of the block, and the sides of all of the studs and recesses being oriented in the same manner.
In accordance with one of the features of the invention, the side walls of the recesses are formed to give the recesses a slight negative taper. That is, the width of the recess opening, at the surface of the block, is slightly less than the width of the recess at a distance from its surface opening. In a similar manner, some or all of the side walls of the projecting studs are configured to provide a slight negative taper, such that the cross section of the stud at the base is slightly smaller than at the top, and at least some of the width dimensions at the top of the stud are at least slightly greater than the width of the openings into the recesses. Accordingly, in order to insert a stud into a recess, the end of the stud has to be forced into the recess opening, and the assembly is accomplished with a tactilly sensible snap action effect. Once assembled, the parts are securely held in place by the fit of the reversely tapered stud and recess walls.
Desirably, the studs are of substantially greater width than height. This is made possible and practicable by relying upon the snap fit interlock of the studs and recesses, to maintain adjacent blocks in assembled relation, rather than relying on a simple friction fit as is customary with such devices. The relatively short projecting length of the studs facilitates disassembly of connected blocks by enabling one block to be more easily tilted with respect to another, providing leverage to effect separation of the interlocking parts.
In an advantageous form of construction toy building block according to the invention, the blocks are formed with opposite side walls which are spaced apart and parallel, and end walls arranged in the form of three sides of an octagon. In a block with a single projection and/or single recess, the body of the block is of octagonal configuration arranged concentrically with the stud and/or recess, with side walls of the block body being parallel with corresponding side walls of the stud and/or recess. For larger blocks, formed with a plurality of sets of studs and/or recesses, the side walls are appropriately elongated.
For a more complete understanding of the above and other features and advantages of the invention, reference should be made to the following detailed description of preferred embodiments of the invention and to the accompanying drawings.